In recent years, expectations for regenerative medicine by cell culture using embryonic stem cells (ES cells), mesenchymal cells, induced pluripotent stem cells (iPS cells), progenitor cells, and the like aimed at differentiation and induction of various cells have been increasing. When cells are cultured, a medium made of a flat plate-shaped substrate has been generally used. As a material being able to be suitably used in this medium and having excellent biocompatibility, there has been proposed a medical material having a polymer brush on the surface of a substrate, the polymer brush being obtained by polymerizing a monomer composition containing N-methacryloyloxyethyl-N,N-dimethylammonium-α-N-methylcarboxy-betaine (for example, see Patent Literature 1).
The above-mentioned medical material shows a small interaction with biological components such as proteins and blood cells, and is excellent in biocompatibility. If cells can be easily cultured in an arbitrary shape on the above-mentioned medical material, it is expected that such culture greatly contributes to regenerative medicine. However, a method for easily manufacturing a cell culture substrate which allows cells to be cultured in an arbitrary shape on the medical material has not yet been established. Therefore, development of such a method is in urgent need.